Technical Abstract:
Achenes are the primary storage tissue for accumulating oil in plants. The composition of the oil determines its suitability for either an edible or industrial use. The genus Helianthus consists of 37 perennial and 14 annual species. It has served as the genetic stock from which the cultivated sunflower has evolved and offers the potential to improve the oil quality of cultivated sunflower. The objective of this study was to determine the oil concentration and fatty acid composition of 25 populations of serpentine sunflower, Helianthus exilis, from serpentine areas of central and northern California. The highest oil concentration was observed in a population from northern CA with 324 g/kg. Four major fatty acids were observed, saturated palmitic and stearic acids, monounsaturated oleic acid, and polyunsaturated linoleic acid. Palmitic acid ranged from 66 to 83 g/kg, while stearic acid varied from 37 to 69 g/kg. Linoleic acid varied from 660 to 761 g/kg and oleic acid varied from 95 to 165 g/kg. The fatty acid profile of H. exilis had a high linoleic concentration (averaging 720 g/kg) for a high temperature environment and southerly latitude. Sufficient variability appears to be present in serpentine sunflower for selection and improvement of the fatty acid composition in the oil of cultivated sunflower.